Spring structure



It- 22, 1940 A. H. HABERSTUMP 2,218,798

SPRING STRUCTURE Filed may 4, 1938 INVENTOR. ALCRE D H. HABERSTU/P- ATTORN EY 5.

Patented Oct. 1940 UNITED STATES PATENT; orrlci;4

SPRING STRUCTURE Alfred H. Haberstump, Detroit, Mich., assignor `to .The Murray Corporation of America, Detroit,

Mich., a corporation of Delaware Application May 4, 1938, Serial No. 205,908

6 Claims.

constructions is entirely eliminated and in whichthe spring elements which form the resilient portions of the cushion are anchored directly into the base frame and serve the purpose not only of providing a resilient surface for the seat cush ion as a whole,but` alsol serve to maintain the 15, surface of the seat cushion resiliently spaced with respect to the base frame. v

Still further, the invention contemplates the provision of a novel base frame construction which may easily and conveniently be formed of -al suitablevsection of sheet metal rolled to the iinal desired form. This base frame has a channel therein adapted to receive a tacking strip and also includes a projecting abutment as well as means immediately beneath said abutment but spaced therefrom for easily and conveniently anchoring the-last lateral convolution of the sinuous spring elements to the base frame.

Manyother and further objects, advantages, and features of the present invention will become nection with the following specifications and the drawing relating` thereto.

In the drawing:

Figure 1 is a top plan View of a seat cushion with portions broken away illustrating one embodiment of the invention. Y

Figure 2 is asectional View taken substantially on the line 2-2 of Figure 1, illustrating in detail the cross-sectional congurationfof the improved seat cushion construction shown in Figure 1.

Figure y3 is a fragmentary perspective view showing a portion of the base frame, illustrating the same in detail.

Figure 4 is a fragmentary perspective view with parts in section, illustrating a modified form of base frame construction embodying a diierent means for anchoring the ends oi the spring element therein,

With more particular reference to the drawy ing, specifically to Figure Lthereo'f, it will be seen that the form of the invention disclosed.

therein includes agenerally rectangular base frame i0 which maybe conveniently made up of four separate frame elements comprising the front and rear sides and the ends, respectively,

5 but which, in the specic form of the invention more clearly apparent when considered in con--V illustrated in Figure l, comprises an integral length or strip of .sheet metal bent to provide a generally rectangular structure. The adjacent abutting ends ofV this strip I0 may be secured together by a sleeve member II which telescopes 5 over the ends and serves the purpose of anchoring the ends in fixed relation with respectto each other to provide a closed, integral, substantially rectangular frame.

By reference'to Figures 2 and 3 of the draw- 10 ing', it Will be seen that the metallicportion of this base frame may be formed from a single strip 'of sheet metal bent upon itself and rolled to provide on its inner side a tacking strip receiving channel I2 having overhanging marginal edges 35 or flanges I3. A suitable tacking strip I4, formed of paper rope or suitable similar fibrous material may be tightly seated in the tacking strip receiving channel I2. The purpose and function of this tackingstrip will become more clearly ap- 20 parent as the description ofthe invention proceeds.

A double thickness iiange I6 of the strip from 'which the base frame is constructed may project exteriorly from the strip and this iiange is bent 25 to provide with the body portion of the strip a springanchoring channel Il, as will be seen by reference to Figure 3. 'I'his ange may be crimped toward the body of the strip at points I8 throughout its length to provide tunnels I9 `for receiving and mounting the springs in the manner hereinafter described in detail.

In addition, the strip Ill is bent to provide an abutment receiving channel 20 which has a paper or ber abutment strip 2l seated therein and, as 35 will be clearly apparent from reference to Figures 2 and 3, this abutment strip projects from The resilientportion of the seat cushion con "o l sists of a plurality of spring elements 25, which elements are each preferablyrformed of a section of spring wire bent upon itself to provide a series of similar adjacent lateral convolutions all lying in substantially the same surface. These spring elements are preferably normalized or initially s'et at the time they are formed sothat they have an inherent tendency as a Whole to lie along an arc of substantially smaller radius than the arc upon which they are disposed when mounted in the spring cushion. Each of these spring elef ments is cut oi to leave a substantially transversely extending last' lateral convolution 21 which, when the spring is assembled, may be yslipped into the channel Il and then laterally through the tunnel I 9, formed by the crimped in portion of the channel I8. In this way, the end of the spring will be rmly anchored in position. The walls of the channel may then be crimped together immediately behind the spring element, as shown at 26, to prevent lateral displacement of the last lateral convolution thereof.

In assembly of the seat cushion, one end oi one of the spring elements is first anchored in the channel l1 at one side oi the base frame in the manner described and then the spring element is tensioned across the frame and the opposite end is anchored in the channel l1 in the opposite side of the frame in a similar manner. The spring element will then engage. the abutment strip A2i so that the spring will assume a configuration substantially as shown in Figure2 of the drawing giving to the cushion construction a very substantial depth and resiliency'.V

After all of the spring elements have been installed in this manner, suitable wire clips 30 may be installed to interconnect the mating portionsy of adjacent spring elements '25 in order to preclude excessive transverse movement of the various spring elements.

In addition to the brace forming a support for the ends of 'the cushion, a wire brace element 3|, having its ends seated in suitable apertures 32 at opposite sides of the frame, mayextend diagon-v ally upwardly and` have its mid portion clipped to the outermost spring member 25 by means of suitable rings 33. This brace member 3l may be of' relatively resilient material in order that it will not materially interfere with vertical flexing of the spring element which it serves tosupport, but, as is obvious from its position and construction. that it will aid in retaining the outermost spring element in substantially predetermined transverse position.

The spring elements 25, which make up the surface structure of the seat cushion, may then be covered with a suitable layer of padding material 35. as is conventional in constructions of this general character and the seatas a whole may be finished by covering the entire exposed surface thereof with a section of suitable fabric iinish material 36 which may be drawngdown over all sides of the cushion and turned up into the interior ofthe base frame i0. The marginal portions of this covering material may then be conveniently secured to the tacking strip I4 by means of tacks 38 thereby providing an exceedingly simple, neat appearing, and highly resilient seat cushion construction.

A modified and somewhat simplified form of base frame member is illustrated in the fragmentary perspective view of Figure 4. In this form of the invention, an abutment receiving channel 40 is formed in the strip and the base of this channel is provided at suitably spaced points with a series of longitudinally extending apertures 4| in order that an abutment strip 42, seated in the abutment strip receiving channel, may serve the dual purpose of providing a tacking strip as well as providing the outwardly projecting abutment 43 about which the spring elements fulcrum to tension them to predetermined desired configuration.

The lower side of this modied form of base frame construction comprises a projecting ange which is bent upon itself to provide an inwardly presented spring receiving channel 45 which is provided with notches 46 in the upper wall thereof at suitably spaced points throughout its length. It will be apparent that the last lateral sioned.

convolution 25 of one of the springelements may be inserted into the spring receiving channel 45 with the spring element extending through the notch 46. As this spring element .is fulcrurned 'about the projecting portion 43 of the abutment strip 42, the end of the spring element will be positively and firmly locked in position within the channel 45 and precluded against bodily relative movement in any direction.

. This somewhat simplified form of base frame construction serves to eliminate the necessity of performing crimping operations on the spring receiving channel in order to lock the spring elements therein. y

Y Many other and further forms and modifications of the invention, falling Within the generic scope of the invention as set forth in the appended claims, will become clearly apparent to vthose skilled in the art.

. What is claimed is:

1. A cushionconstruction comprising a base frame, a plurality of spring elements each formedv of a section of spring wire bent sinuously to provide a series of similar `adjacent lateral convolutions, said springv elements being disposed substantially parallel to each other and each having their extreme ends anchored to said frame at opposite outer sides thereof, and abutments on said frame serving to engage said spring elements at a point above and outwardly of theirpoint of anchorage to tension the same to the lpredetermined desired configuration..

2. A base frame for seatv cushion constructions comprising a sheet metal strip preformed to pro- K vide means for anchoring the endsV of spring elements therein and an abutment carried by said strip spaced above and projecting over said anchoring means and over which the spring is ten- 3. A cushion construction comprising a base frame having means formed therein for anchoring wire spring elements, abutments carried by said base frame spaced above and projecting outwardly over said anchoring means, a plurality of spring elements each comprising a section of spring Wire bent to provide a similar series of adjacent lateral, convolutions, one end of each of said spring elements being anchored in said anchoring means and extending upwardly therefrom and engaging said abutment, said spring element extending across said frame and downwardly over the abutment at the opposite side and having its opposite end anchored in the anchoring means. v

4. A base frame for seat cushion constructions comprising a sheet metal strip bent upon itself to provide a channel having overhanging side Walls, an abutment strip formed of fibrous material seated in said channel and anchored therein by means of said overhanging side walls, said abutment strip having a portion projecting from between said walls, and means formed in said sheet metal strip beneath the projecting portion of said abutment strip for anchoring the ends of spring elements. l

5. Abase frame :for seat constructions comprising a Vsheet metal strip bent upon itself to provide a channel having overhanging side walls, an abutment strip formed of brous material seated in said channel and anchored therein by said overhanging side Walls, said abutment strip having a portion projecting between said side walls, the base of said channel having a series of apertures therein whereby said abutment strip may serve as a tacking strip, and means formed in said sheetl metal strip beneath the'projecting portion of said abutment strip for anchoring the thereof, and a spring spanning the opposite sides of said frane and drawn over said abutments` and secured by said anchoring means at both sides of the frame to tension and provi'de a predetermined conguration thereto.

mm3 H. HABERSTUW. 

